Automatic ice making apparatus



Jan. 17, 1956 A. L. MURDOCK 2,730,365

AUTOMATIC ICE MAKING APPARATUS Filed Feb. 26, 1952 2 Sheets-Sheet I FIG. 1 62 CONDENSER.

COM PRES 50R.

Fica. 3

, INVENTOR. Alberc L.Murdock QMIMV6II Aflorney Jan. 17, 1956 A. L. MURDOCK AUTOMATIC ICE MAKING APPARATUS 2 Sheets-Sheet 2 Filed Feb. 26, 1952 INVENTOR. Alberc L. Murdock Ai'forn ey United States Patent AUTOMATIC ICE MAKING APPARATUS Albert L. Murdock, Durham, N. C.

Application February 26, 1952, Serial No. 273,379

7 Claims. (Cl. 62--2) This invention relates to ice making machines and more particularly to an improved automatic machine for making ice and handling the same.

Automatic ice machines for making flake ice and for making ice cubes are well known. Most of these are constructed on the principle of forming a sheet of ice on a revolving drum orin divided pans, and operate on a time cycle in which the ice is scraped or loosened from the drum or dumped from the pans after a fixed time interval. It is known that the thickness of ice formed in a given time interval varies in accordance with variations in the temperature of the water used and the temperature of refrigerated surface upon which the ice is formed. i

It is an object of this invention to provide an automatic ice making machine in which the weight of the ice produced in one cycle of the machine is maintained constant.

It is a further object of this invention to provide an automatic ice making machine in which the length of the freezing cycle is controlled by the weight of the ice produced.

It is another object of this invention to provide an automaticice making machine in which ice is formed on one or more suspended and refrigerated plates upon which cold water is caused to impinge and freeze.

Numerous other objects and advantages of u the invention will be readily apparent to those skilledin the art from the following detailed description of preferred embodiments of the invention illustrated in the accompanying drawings, wherein:

Figure 1 is a sectional view, partly diagrammatic, of a preferred form of the automatic ice making machine of this invention;

Figure 2 is a sectional view taken on line 2-2 of Figure 1;

Figure 3 is a plan view of the freeze plate supporting linkage shown in Figures 1 and 2;

Figure 4 is a sectional view similar to Figure 2 but illustrating a modified form of ice making machine;

.Figure 5 is a sectional view of another modification of the automatic ice making machine shown in Figures 1 and 2;

Figure 6 is a side elevational view of one of the freezing plates shown in Figure 5;

Figure 7 is an end elevation of the freeze plate shown in Figure 6; t

Figure 8 is an elevational view of a modified form of freeze plate adapted for use in any of the automatic ice making machines illustrated herein; and,

Figure 9 is an end elevation of the modified freeze plate shown in Figure 8.

Referring to Figure l for the purposes of illustration, the ice making machine is provided with a casing designated by the numeral 10. The casing 10 may be ther mally insulated.

A hollow freezing plate 11 is suspended in the upper part of the casing 10. The hollow plate 11 is provided with a flexible inlet conduit 12 for' the admission of a fluid refrigerant, and is provided with 2,730,865 Patented Jan. 17, 1956 a flexible outlet conduit 13 for the exhaust of expended refrigerant. The hollow plate 11 may have a zigzag internal cooling coil therein connected to the inlet 12 and outlet 13. The lower part of easing it) forms a reservoir for cold water 14, and may be provided with a cooling coil 15 through which liquid refrigerant flows to cool the water 14. At one end of the water reservoir 14 is a closed casing forming a suction trap 16. The suction trap 16 is adapted to contain liquid refrigerant 17 in its lower portion. The upper portion of trap 16 is connected by a conduit 18 to the inlet or suction side of a conventional refrigerant compressor 23, and is also connected to the plate outlet conduit 13 by connection 19, and to the cooling coil 15 by connection 29. A conven tional float-control inlet valve 21 is provided to control the inlet 22 of liquid refrigerant to the trap 16 for maintaining a constant level of liquid refrigerant in the trap 16.

At the bottom of water reservoir 14 is a cold water outlet 25 connected to a pump 26 which pumps cold water through conduit 27 to a spray nozzle 28 through which cold water is directed against the lower surface of freezing plate 11. A solenoid-operated valve 29 is provided in the conduit 27. A V-shaped perforated ice collector or hopper plate 30 is supported within the casing 10 above the level of the cold water 14, and may be provided in its lower portion with a conveyor screw 31 driven by a motor 32 at the end of the casing 10. The casing 10 is provided with an outlet aperture 33 at the end of the conveyor 31 and through which ice may be delivered to an ice crusher 34 on the conveyor shaft, the ice being discharged downward through a delivery opening 35. The crusher 34 may be eliminated in installations where ice crushing is not required. The icecollecting plates 30 are perforated in order that any cold water dripping from the freezing plate 11 may flow back to the cold water reservoir 14 for recirculation. The level of the cold water in reservoir 14 may be maintained constant by an atuornatic float-controlled water inlet valve 36.

The high pressure side of compressor 23 is connected by conduit 40 to a conventional condenser 41. Liquid refrigerant from condenser 41 flows through conduit 42 to the flexible inlet connection 12 for the freeze plate 11. A solenoid-operated cut-otf valve 43 and an expansion valve 44 are provided in conduit 42. The expansion valve 44 may be variable and be controlled by a thermal control device 45 responsive to the temperature of refrigerant in the outlet connection 13. A hot gas bypass conduit 46 extends from the conduit 40 through a solenoid-operated valve 47 to the conduit 42 between expansion valve 44 and the inlet connection 12. The by-pass 46 is provided to permit the introduction of hot refrigerant gases into the cooling coil in freeze plate 11 momentarily when it is desired to release the ice frozen on the plate 11. u

The support of the freeze plate 11 within the casing 10 will now be described. The plate 11 is preferably suspended by four links or cables 50, one attached to each cornerof the plate 11. The upper ends of the links 50 are secured to horizontal beam members 51 and 52, shown best in Figure 3. The outer ends of the beams 51 and 52 are suspended by links 53 and 54, respectively, secured to brackets mounted on the casing 10. The adjacent ends of the beams 51 and 52 rest upon a connecting member 56, which in turn is suspended by a link 57 extending upward through the removable cover 55 to the end of, a scale beam 58. The scale beam 58 is pivotally supported by a pivot 59 carried by a horizontal bar 61 mounted in the casing 10. The beam 53 is provided with. an adjustable weight 60. The weight 60 is slidable along the beam 58 to counterbalance the weight of the beams 51 and 52,.

and the freeze plate 11 and to provide overbalance in an amount equate the desired weight of ice to be formed on freeze plate 11 during each freezing cycle of opera tion. The beam 58 is connected to Operate a switch mechanism 62 which latter is connected to supply line 63' and controls the operation of the solenoid valves 29 43, and 47, heretofore described. 7 I

The'operation of the automatic ice making machine illustrated in Figures 1, 2 and 3 will now be described. The refrigeration apparatus including compressor 23 and condenser 41 and controls therefor may be conventional. Refriger'an'ts such as ammonia, Freon, and the like may be used, as will be obvious to those skilled in the refrigeration art. The water 14 to be made into ice is stored in the tank forming the bottom of casing 10. The water 14' is precooled by the cooling pipes 15 containing liquid refrigerant 17 from the trapchamber 16. The pipes 15. are spaced well apart so that any ice'formin'g on the pipes will not prevent the flow of water" over and betweenthe pipes. The water thus cooled, is pumped by pump 26 to the nozzle 28'which directs'it against the lower side of freezeplate 11. The freeze plate 11 is refrigerated to freezing temperatures by the flow of refrigerant through the expansion valve 44 into the hollow plate 11. The spent refrigerant passes out of the plate 11 through the lower connection 13 andinto the trap chamber 16. Gaseous refrigerant is drawn from the upper part of trap 16 through conduit 18'into the compressor 23 for recycling in the system. The level of liquid refrigerant maintained in the bottom of trap 16 is controlled by a conventional float valve 21 admitting liquid" refrigerant from the line 63 to the trap inlet'22. When ice has frozen on the freeze plate 11 to the desired weightof ice, the weight of the ice'causes the plate to move downwardoverbalancingthe adjustable counterweight'on beam 58 and causing the switch mechanism 62 to function. Switch mechanism 62 then closes the valve 43 to stop the flow of refrigerant to the plate; opens thevalve 47 to'permit the flow of h ot refrigerant gases to the freeze plate, and closes the valve 29 to cut off'the flow of cold water to the spray nozzle 28. The admission of 'hotgas to the plate 11 quickly causes the'ice'formed" thereon to drop off onto the perforated hopper 30 and conveyor 31which moves the ice to the crusher 34, or to a suitable storage container. if desired. Anywater unfrozen by the plate '11'or formed during the thawing step passes downward'th'rough the perforations in the hopper 30 an'd'ba'ck'to the water st orage spaceiin the bottom of the casing-'10; As soon as the ice has dropped off from the plate 11, the adjustable weighlt 6j0 rais'es'the' plate 11, and' operates the switchmechanism 6 2'to' cut offthe hot gas valve 47, open the refrigerant v'alve'43, and'open'the cold waterspray valve;29, to start the formation of more ice on the'plate. Thelthawin g' operation is relatively rapid and the amount of hot gas introduced into the plate 11 and the trap 16 is 'small and not enough' to unbalance the system. The expansion valve" 44 may be controlled by mechanism 45 responsive to the 'temp'e'ratureof the freeze plate exhaust13 to rnaintain the desiredfreeze' temperature'of the plate 11. The

water supply valve 36 operates automatically to maintain the'water level'constant. The nio'tor'32 operatingthe ice discharg'e'conveyorfil may be operated periodically on atime cycle, or may be operatedonly when ice is desired, or'may 'be' controlled automatically to discharge ice only after 'adesired quantity of ice hasbeen formed. When ice dropsfrom'the freeze plate 11 ontothe hopperSO- and conveyor31, it may break into pieces of satisfactory size and eliminate the needfor the crusher 34in" certain installations. It will beno'ted'thatby adjustmentofthe position of th'ebalanceweight '60 on the scale beam 5 8,

theicem'aking may be controlledto' form ice of most any,

desired thickness before "the'switch mechanism 62 func tlons'autornatically'to control the thawingcyclej m1 -modified"forni'of antomatic ice makingirnaehirre shown 11 Fig'nre'4; thedetails are the same as in'the l machin'e excpt'thatthe hopper and conveyor are replaced by a sloping perforated plate 65 which serves tb'peffnif the" ice to Slide by gravity to discharge opening 66 and into an accessible open bin 67 for use.

In the modification shown in Figure 5, a plurality of vertical freeze plates 71 are used instead of a single inclined plate 11. Each plate 71 is suspended from the beam members 51 and 52 by links or cables 72, so that the Weight of ice formed on the plates 71 will operate the switch mechanisrn 62 when a; desired weight of ice has been formed In this modification, each vertical plate 71 is provided with"ahorizont'al water distribution conduit 73 along its upper edge, the conduits 73 being perforated to flow" water down bothside surfaces of each" plate 71 for freezing. The spray nozzle 28 of the preferred modification is not used, and the conduits 73 are connected together and through a flexible conduit 74 to the water control valve 29, The plates 71 are provided with an' internal refrigerant coil and with refrigerant inlet and be easily substitutedon any'rofthe' freeze platesillustrated.

Thisinvention contemplates'the use" of variouslfjor'rns of weighing mechanisms, switch mechanisms, solenoid valves, and lthe lik'e,-a's'it will be readily apparent t'o'the skilledrefrigeration mechanic that many siich 'siibstitu' tions'and variations are possible within the scope of the followingclaims.

1. In automatic ice' makingapparatus, the combination comprising, a housing, a refrigerated hollow plate main: ber adapted to freeze water applied to the lower OlllIfSlII- face'of said member, a pivotally'mountedlinkage in thfe' upper portion of said housing and having said hollow' plate member: suspended therefrom, a cold wate'rre en voir in the bottom of 'said housing, pump means'to 'ap ply water from said reservoir to the lower surface of said platemember', refrigerating means to csqrsaiama iber; switch means 'enga'ged'by said'linkage for cutting off' refrigerating means upon formation of afpred'ter weight of iceupon'saidmernber, and'a perforateh' per within said housing below said member and suave said water reservoir for collecting ice formed ons aidme 'b'r.

2. In automatic icemaking apparatus, the combina n comprising, a housing, a refrigerated hollow plate stem: ber adapt'edto freeze water applied to the lowerfouter surface of said member, a' pivotally' mounted sealef be'arn type linkage" at the upper end of said'housing, means sus pending said plate member from saidlinkageinfaposi tio'n finclined withrespectte 'aIhorizontal plane, 1110 21 me'a'ns'to spray'w'a te'r againsnne lower outer surface of said plate member, refrigerating means to cool sai d'jpla'te membenan'd means connected to said plate memberf'sup, porting linkage, to said refrigerating'means, andftoeaid water spray means to cut off said refrigerating mfeans and spray means upon formation of a predetermined weight of'ice'upon said "plate member. I i I t I 1 3. Inautomatic ice making.- apparatus, the combination comprising, a hollow plate member, counterbal ced linkage means for supporting said plate rnember,inlet'iand outlet conduits connected to said platemernber, a valve" connected to said inlet conduit for admitting a refrigerant, to 'saidpl'ate member, a second valve connectedto inlefconduit forv admittinga relatively gas to said plate member, means for directingiw ater against an outer surface of said plate, and'meanscontrolled by s ai d linkage for closing-said refrigerant valve and opening said:

hot gas valve upon formation of a predetermined weight of ice upon said plate member.

4. Automatic ice making apparatus comprising in com bination, a housing, a hollow plate member adapted to freeze Water applied to the surface of said member, counterbalanced linkage means at the upper portion of said housing for supporting said plate member, a cold water reservoir in the lower portion of said housing, a pump connected to said reservoir for delivering water from said reservoir to said plate member, refrigerating means including a compressor and a condenser, a liquid refrigerant trap chamber extending into said water reservoir, a cooling conduit in said water reservoir connected with said trap chamber, conduits connecting the upper portion of said trap chamber with said plate member and with the inlet of said compressor, a conduit connecting the outlet of said compressor to said condenser, a conduit connecting said condenser to said plate member and having a cut-off valve and an expansion valve therein, a conduit connecting the outlet of said compressor with said plate member and having a cut-off valve therein, and means operated by said linkage and connected to control both of said cut-01f valves, whereby upon formation of a predetermined weight of ice on said plate member said first cut-off valve is closed to stop the flow of cool refrigerant to said plate member and said second cut-off valve is opened to admit relatively hot refrigerant from said compressor to said plate member to release ice from the surface of said plate member.

5. In automatic ice making apparatus of the character defined in claim 1, said perforate hopper being flat and inclined with respect to a horizontal plane and having its lower portion aligned with a bin outside of said housing.

6. In automatic ice making apparatus, the combination comprising, a reservoir for cold water, a hollow plate member, a conduit for directing cold water from said reservoir against the surface of said hollow plate member, a refrigerant supply conduit connected to said hollow plate member, a valve in said cold water conduit, a valve in said refrigerant supply conduit, a balanced linkage supporting said hollow plate member above the level of water in said reservoir, and valve control means engaged by said linkage and connected to both of said valves to close both of said valves upon formation of a predetermined weight of ice upon the surface of said plate memher.

7. In automatic ice making apparatus, the combination comprising, a reservoir for cold water, a hollow plate member, a conduit for directing cold water from said reservoir against the surface of said hollow plate member, a refrigerant supply conduit connected to said hollow plate member, a valve in said cold water conduit, a valve in said refrigerant supply conduit, a balanced linkage supporting said hollow plate member above the level of water in said reservoir and in a position inclined with respect to a horizontal plane, a nozzle on said cold water supply conduit for directing cold water against the lower outer surface of said inclined plate member, a perforate sheet positioned between said inclined plate and the surface of the cold Water in said reservoir, said perforate sheet also being supported in a position inclined with respect to a horizontal plane to direct ice falling from said plate mem ber to one side of said reservoir, and valve control means engaged by said linkage and connected to both of said valves to close 00th of said valves upon formation of a predetermined weight of ice upon the surface of said plate member.

References Cited in the file of this patent UNITED STATES PATENTS 1,815,383 Scullen July 21, 1931 2,086,622 Kagi July 13, 1937 2,105,460 Gaugler Jan. 11, 1938 2,239,234 Kubaugh Apr. 22, 1941 2,340,721 Whitney Feb. 1, 1944 2,429,851 Swann Oct. 28, 1947 2,511,419 Smith June 13, 1950 2,549,747 Leeson Apr. 17, 1951 

